I find it horribly fascinating how entrenched these gender stereotypes are in our society. They were fizzling out for a bit but have come back with a vengeance, arguably especially for girls who had made most progress and are now back in a female=long hair box, but of course most boys never even made it out of the box in the first place.
It's almost unbelievable that any adult could listen to that 11 year old and not remind them almost reflexively that you don't have to like any colour or particular activities to be a boy. But no, nod along Daniel.
Friends of the family in the US have a daughter who is transitioning at the moment. As children the boys were dressed as mini-mes of their dad, played sports and were always being praised for being tall and strong. The daughter had long curled or braided hair, really impractical dresses on any time I saw her and the mother was clearly uncomfortable that she were also tall and strong like her dad. It felt like she was always being squashed down.
Anyway, same sex attracted daughter is now a straight boy - hurrah! And they're hugely supportive and daughter says she's now so happy that she's her true self, so that's great... I dunno, maybe there were other ways of being a girl that she never grew up to learn and they just can't see.